IMSAI 8080

From: Allison J Parent <allisonp_at_world.std.com>
Date: Tue Jun 23 08:16:00 1998

<Shure, but where ? Just on a disk ? I already have the problem
<that I can't read some fd's of the early 80s. Even APPLE II disks,
<althrough I always said that a DISK ][ drive could read and write
<anything including Bierdeckl (beer mats/coasters).

Disks on good equipment are as reliable as Magtape.

<PBS Tapes from 1976 and they are still readable, but they are

I have floppies from then to bot readable and not. more are readable
than not.

What that means is every ten years update to new media to preserve the
data.

<Or just put it again on EPROMS - with propper handling
<EPROMS could survive at least 50+ years - and PROMS

Maybe... they realy on charge storage and that can dissapate in time.
Also xrays, cosmic rays and whatever can erase them! This does not
include the ambient moisture getting to the silicon and rendering it to
sand.

<(real one not EPROMS without window) should live even

Fuse link proms were even worse. I've had them grow back or develope
other defects over time. AIM proms are better but still if overstressed
at programming they can exhibit failure over time.

<longer. So just copy them. And beside the information -
<it will be even more dificult to get a usable 2704 or
<2708 not already needed for an old computer.

In the case of 27xx devices, if they forget reprogram the same one if
it's still good. If it failed well... find another?

<> takes a dry joint on the ground pin of a 7805 ( or worse still, loose
<> screws on the TO3 canned version) to wipe out the entire board of IC's
<
<> If you think I'm paranoid about this, I am. I've had it happen, you see
<> and I don't want it to happen again.

I've also had those regulators drift with age. Like any IC they can fail
of many ways!

Allison
Received on Tue Jun 23 1998 - 08:16:00 BST

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